What does that mean? Well, his metaphorical advice is actually quite simple: If you have small hesitations about the partner you’re with, don’t ignore them. The deeper into the relationship you get, the more important those concerns become. Of course, many conflicts can be worked through; part of growing a relationship is engaging in compromise and forgiveness. If you ran away from every partner who wasn’t absolutely perfect, you’d be flitting from person to person until you finally gave up. And, as D’Arienzo points out, people can change.

“It’s certainly normal to experience a range of emotions when dating someone new,” D’Arienzo told The Daily Meal in a phone interview. “One’s statuses at 20 do not always determine who they will become at 30 and 40.”

But there’s one trait he recommends you consider as an immediate marriage deal breaker.

“If you encounter traits or histories about the person you are dating that you can’t share with your friends and family,” he advised, “then they should not make the cut.”

Dark secrets lurk in many of the relationships D’Arienzo encounters in his work as a psychologist and relationship expert. It’s these hidden qualities that end up driving the relationship awry.

“I’ve seen it all,” he said. “People can be pillars of the community, outstanding citizens from the outside looking in. But on the inside, anything could be going on. I’ve talked with couples where they’re hiding that they’re cheaters or have a whole second family. Nothing surprises me anymore.”

It all comes down to your values, D’Arienzo explained. If you’re ashamed of some of your partner’s traits, that’s a strong signal that your values are misaligned and it could become increasingly difficult to start a life together.

There are some exceptions to this rule. “If you have a family or friends who are exceptionally traditional or conservative,” said D’Arienzo, “you might choose to hide certain things about the person you’re seeing. But if your values match those of your family and you’re still keeping something from them, that’s when you know that something is wrong.”